Center punch



H. C. REHM CENTER PUNCH Filed Sept. 16, 1927 buraalor Barri/010k)! Patented Oct. '7, 1930 U E 1 STAT s. AI -E T. oFFiCE; f

HARRY c. REHI/li, or m Wayne, INDIANA, ssIGNon 'ro THE L. s. seamen-"co ,PANY; on ATI-IOL, MASSACHUSETTS, A CORPORATION or MASSACHUSETTS- CENTER rumor: j a

' Application filed september 16;.1927. Serla1 No. 218,874.

The invention herein presented-while involving in-its more specific phase an improvement in spacing center punches has certain features of novelty of more general application. As the improved center punch involves a very practical advantage and also illustrates advantageously the broader principles involved; I will discuss my invention in this 7 more specific form which is illustrated in the accompanying drawings. w;

In the use of spacing center punch such as is herein shown, it is wellknown' to mechan ics that they tend to lose accuracy of adjustment with a corresponding variation in spacing. In this the center punch afiords a highly characteristic example because from the nature of its use it is subjected to blows whichtend to move the adjusting parts. Furthermore, it is frequently desired in. such -2 adjustable devices to make a slight change in adjustment and to make that change with certainty and definiteness,v In accordance a a with my invention I have thereforeprovided a locking effect by Which at the same time a, ,i certainpredetermined movement of the adjusting parts can be effected so that the work man does not have to rely on his own sense of touch, but is enabledto make a positive move; ment with definite limitation. 1

In the drawings I have illustrated a certain center punch of wellknown make and shown in connection with it my invention applied as 'an improvement thereto; I have illustrated this center punchin some: detail in spite of the fact that thepunch in general is an old and established article onthe-market, because my improvement while: involving only a very slightchange in the old and well known punch produces novelcombinations with'the old parts which gives them-new functions as I will hereinafter describe. In thedrawingsr j a I j V Fig. l'is a side elevation of the center punch above referred to. j V Fig. 2 is aipartly' sectioned fragment'of the punch showing the adjustment thereof, and Fig. 3 is an end view of the threaded ad justing member viewed'from the end so as to expose the under sideof the knurled lnead. I ,The spacing center punch shown comprises a punch member consisting a knurled portion 1 having a head 2 anda point 3. Ate tached tothe body portion l'by a screw tie a bent guide arm 5' having its free end 5} formed to receivea point 6 slidable-within the springs. g; j I j a Fixed on the guide 5 is a pin 7 which. passes through the punch 1 projecting slightpart 5 and. normally protruded, by a ly' on the other side thereof and within the margin of the head8 of an adjustingimempin 7. Asthe member 8;is turned toscrew it in or out of thepunch body 1, its head 8 her 8. "This adjusting member is threaded r V bears on the free end of the. pin 7 toforce out" the guide arm 5 to separate its point 6 from the point 3 of thepunch sojas to. cause the desired degree of spacingbetweenthe point 6 andthe point Bjof thepunch. In this movement the adjustment is resistedby the resilience of the armelwhich yields in I the bent portion 5 thereof and whichresilienceg tends to hold the pin 7 againstthe knurled head 8 All of this structure shown is old in thestandardspacing center punch which I have heretofore referred to aslong on the marketand in very general use.

My invention contemplates; the conversion ofsuch a punch into an improved deviceby simply formingon the under, face of the head 8 a series of recessesonindentations 9 so disposed as to successively pass the free end of the pin 7-when thehead 8 is rotated.

By, the simple introduction of these recesses I convertthe pin'7 into a spring pressed detent. which locks the head 8 against rotation so that it will not be 'moved under the shocklof thehammer blows. In this function itwillb'e noted that vthe resilience of the guide'arm 5 provides theurge onthe pin 7 in its actionas a detent and conversely allows itto yield slightly when the head :8 is r0- tated, so that the point of the pin 7 can clearone I'BCGSSgQ flS' the head 8 is rotated prior to thealignment of the next recess 9 w'ith which the pin end will engage as soonas the next recess comes under the pin end. I a a The recesses 9 in addition to this locking 7 feature provide a seriesof points at which rotation by any slip of the fingers of the operator. .7, "It willthereforebe seen that in the specific embodiment shown Ihave beenable by' the mere addition of a series of indentations to greatly improve an existent device wlthout adding material costv or expense, in the'eprOr duction of the same. In thisfphase o'f my invention alone. there is a definite-improve' Inent which-is-immediately' available. 7 My invention is capable of-use' in othersimilar structures and like devicestoeffect like ad vantagesand without adding'gmaterially to the cost involved in manufacturei 7 What I therefore claim and desiregtjof se cure by Letters Patent is: 1

1. In a spacing center 'punchya punch, a spring guide arm thereon, an adju ting screw c'arriedby said punch and including ahead,

a thrust connection between thespring arm and head, said head having a plurality of receiving notchesdis'posed about one'face thereof for successive engagement with said thrust connection 'upon rotation of said screw.

2.- In a-spacin-g' center punch, a punch, a

spring guidearrn thereon, apin on'sa-id arm and extending through said fpunch, an ada justingf screw carried' by saifd'punch and including a head disposed tofoverli'esaid pin and having a plurality of receiving notches disposed about its pin contacting face for successive engagement with said pin upon rotation of said screw. 1 Y I 3'. Ina spacing center punch, a punch, a spring guide arm thereon, an adjusting d'evice including a rotatable member carried by said'pun'ch and athrust memberffixedjto said spring uide arm, said rotatable member having a p urality'of receiving notches disposed about one facet-hereof for successive engagement'with said thrust member upon rotation of said rotatablememberi- I v 4. Ina spacing punch,-'a"pun'ch member, a spring arm carried thereby, apin fast'ened at one end to said arm, an adjusting member carried by said p'un'ch member and terminatin'giin a head disposed 'in aplane transverse to the axis of the pin and presenting a notched bearing surface adapted to press against the free end of'the' pinupon rotationoffthe adjusting member-in one direction and force'the spring'arm away from the punch member a distance corresponding to the degree of rotation of the head as sensitively indicated to the mechanic by the passage of'the notches over the free end'ofthe pin and said spring arm returningtowards the punch member under its own spring action to raise th e pin to lodge in a notch opposite thereto and lock the head against accidental rotation.

5. In a device of the class described, a pair of relatively yielding arms, a spacing device including a rotatable adjusting head on one of said arms and'havinga' plurality ofreceiving notches and'a spacer pin on the other of said arms and disposed beyond the first'mentioned arm but yieldingly contacting said head'inthe path of said notches. 6; 'In'a" spacing punch, a punch member, a spring arm carried thereby, a thrust memberc-arried by said spring arm, and a rotatable member carried by said punch memher and having a head disposed in a plane transverse to the axis of the thrust member and presenting a bearing surface'adapted to press against the free end oi said thrust member upon rotation of said rotatable member in one direction and force-the spring arm away from the punch member.

7. In a spacing punch, a punch member, a spring arm carried thereby, athrustmemberjcarried by said spring arm, and a rotatable member journaled in said punch member with its axis of rotationparallel. to the thrust member, said rotatable member having a head disposed in a plane transverse to the axis of the thrust member and presenting a bearing surface adapted .to press against the free end of the thrust member upon rotation of the rotatable member in one direction'to force the spring arm away from the punch member. 8. In a spacing punch, a punch member and a spring arm carried thereby, said punch member having spaced parallel trans verse 'bores,-an adjusting member threadedly mounted in one of said bores and having a head provided with an annular series of spaced recesses, an elongated spacing member fixed at one end to said spring arm and extending through the other bore of the punch member and having its free end projecting sufliciently beyond said punch memher to be successively engaged in the rec'esses of said head as'the rotatable member is rotated relative to said elongated spacing member.

9. Ina spacing punch, a pair or relatively 'yieldable arms, and a spacing device there for including a relatively fixed member carried by one of said arms and arelatively rotatable member threadedly carried by the other arm,- said relatively rotatable member terminating in a head disposed in a plane transverse to the axis of the relatively fixed member, and saidheadconstituting a grasping portion whereby said rotatable member may be rotated and a bearing surface adapted to press against the free end of said rela tively fixed member to effect separatioifoi' the pair of arms upon rotation of the ro tatable member in one direction, 10. In a spacing punch, apair of rela ioo tively yieldable arms, and a spacing device therefor including a relatively fixed member carried by one of said arms and a relatively rotatable member threadedly carried by the other arm, said relatively rotatable member terminating in a head disposed in a plane transverse to the axis of the relatively fixed member, and saidhead consti tuting a grasping portion whereby said rotatable member may be rotated and a bearing surface adapted to press against the free end of said relatively fixed member to efiect separation of the pair of arms upon rotation of the rotatable member in one direction, the bearing surface of said head having spaced formations permitting it to ride over the free end of said relatively fixed member and to be yieldingly locked by said relatively fixed member at selected phases of rotation of said head.

11. In'a spacing punch, a pair of relatively yieldable arms, a rotatable member carried by one of said armsand formed to present an enlarged portion provided with a locking recess, a locking detent fixed on the opposite arm and extending parallel to the axis of rotation of said rotatable member and having its free end disposed for engagement in said recess of the rotatable member upon rotation of said rotatable member relative to said locking detent.

12. In a spacing punch, a punch member having a transverse bore, and a spring arm secured thereto, a screw set through said punch member and having ahead provided with an annular series of spaced recesses, a pin fixed at one end to said spring arm and extending through the bore of said punch member parallel to the axis of rotation of said screw with its'free e'nd projecting suf ficiently beyond said punch member to be successively engaged in the recesses of said head as the screw is rotated relative to the pin.

13. In a spacing punch, a pairof relatively yieldable arms, an elongated spacing member fixed to one of saidarms, an adjusting member rotatably mounted on the opposite arm and provided with a head having an annular series of spaced recesses disposed to ratchet past the free end of said spacing member upon rotation of said head relative thereto andsaid annular series of recesses constituting an 1nd1cator to indicate definitely to the mechanic predeter mined distances of rotation of the head relative to the spacing member. 7

In testimony whereof I affix my signature; *HARRY C. REHM. 

